This is the second in a series of dispatches on Afghanistan in retrograde, stories documenting the logistical withdrawal of U.S. forces and matériel from the war-torn country. Retrograde is a military term for the dismantling of installations.

Throughout history, one of the most difficult maneuvers to pull off in combat has been the fighting withdrawal. It’s an aspect of war that plagued battlefield commanders from Napoleon to Lee to Bradley. Getting into a fight is easy; getting out usually presents a challenge and particular dangers.

Every infantryman and combat soldier knows the concept of breaking contact. It is a battle drill practiced over and over: one part of the unit fights on while the other part pulls back, and in a carefully coordinated (though often chaotic) leapfrog, the soldiers extract themselves from harm’s way.

That’s how it has worked historically, at least, when armies met in uniforms on actual fields. After nearly every such battle, one could usually declare a winner and a loser. But today’s asymmetrical wars are messy, and for some time now, the U.S. mission in Afghanistan has shifted from a counterinsurgency fight to a partnership, preparing Afghan forces for when American troops go home. But as U.S. units break contact, a large component of leaving the battlefield is bringing back the myriad pieces of equipment the Pentagon has pushed out to small outposts over the past few years.

In eastern Afghanistan, no one knows this mission better than Bull Battery, an airborne field artillery unit in the 173rd Airborne Brigade. During previous rotations in Afghanistan, Bull Battery’s troops fired big guns in support of maneuvers, and they often conducted counterinsurgency missions themselves. Then early in this tour, the battery established its reputation as the unit that can accomplish retrograde, the missions that are the heart of overall U.S. withdrawal from Afghanistan.

For the past month, the soldiers of Bull Battery have been working to hand Forward Operating Base Altimur over to the Afghans. A hunk of land on the slope above a wide desert valley, deep in Logar province, Altimur looks out on craggy, snow-sprinkled mountains that wouldn’t look out of place in Utah or southern Idaho. Originally the size of about three football fields, Altimur was home to roughly 300 soldiers before they began “descoping” the base, pulling out the majority of the American equipment and drawing down to a size that’s manageable for the Afghan unit that will take it over.

It is the first of those tasks that now takes up most of Bull Battery’s time. As bases go in Afghanistan, Altimur is somewhere in the middle in terms of size. It is far smaller than Forward Operating Base Shank, the logistics hub for Logar province, but bigger than the outposts where many of the units lived until a short time ago. Like many bases in Afghanistan, of all sizes, Altimur was packed with equipment, mainly so that troops could fight from there when being resupplied was difficult.

“If you look at how challenging Afghanistan can be in the winter, how challenging transportation can be, every node, in some way, has to become its own little repository of supply,” says Lieut. Colonel Kelly Webster, commander of 4-319 Airborne Field Artillery Battalion, Bull Battery’s parent unit. Having copious supplies allowed units “to be able to weather over periods where you can’t get resupplied,” Webster explains. But now that the troops are leaving Altimur, getting that equipment from Altimur to larger bases, and on the way out of the country, becomes a big, complicated operation.

Webster chose Bull Battery to handle the main part of that push because they had already done it in smaller, but much more hostile conditions. Last year, Bull Battery moved out to Combat Outpost Garda, a horseshoe-shaped scrap of land in a hotly contested area in Wardak province. Soon after, they got the mission to close the outpost and move everything to a bigger base.

Captain Thomas Feeney, Bull Battery’s commander, started by figuring out what could go immediately. “We identified what is mission essential, and when you really break it down that’s not a whole lot of stuff,” Feeney says. “It’s food, bullets, water, and most of the other stuff can go.”

During the first few times convoys left the base, rocket-propelled grenades came flying from insurgents, and the troops soon started mixing up departure times. Sometimes, a convoy would pull out just after sunset; other times, one would leave at 3 a.m. The troops still did joint patrols with Afghan government units, so often they would patrol by day and retrograde by night, sling-loading equipment onto helicopters in the darkness so the birds were harder targets for insurgents.

The enemy attacked Garda often, forcing the troops to fight one minute, then go back to the mundane tasks of inventorying and packing equipment the next. “It’s really stressful, and it’s actually really tiring,” says Sergeant Mario Diaz, one of the noncommissioned officers who oversaw much of the retrograde tasks. “That flip-flopping back and forth, it gets aggravating. You get real irritated real quick.” After more than a month of a fighting retrograde, few troops from Bull Battery were disappointed to see Combat Outpost Garda in their rearview mirror.

In Altimur, every day for the past month, the paratroopers of Bull Battery have been doing the hard slog of moving thousands of pieces of equipment on hundreds of trucks, to Forward Operating Base Shank across the desert valley below. Every morning, a sergeant rouses dozens of Afghan truck drivers from a yard beside the base. Though they have a small shack, many sleep in their trucks to keep the engines running throughout the night, as they often fill the radiators with water and don’t want the engines to freeze.

Throughout the day, the troops and a few civilian contractors load truck after truck with T-walls — 2.4-m-tall slabs of thick concrete that surrounded most buildings when the base had to accommodate the American contingents. (A few T-walls will be left to help protect the smaller Afghan army base.) The drivers can fit four of the walls on the flatbed of their trucks, or two 6-m metal containers, or four heaping pallets of 3-m-long lumber. Load by load, the base grows smaller, and soon it will be about a quarter of its original size.

The equipment that leaves Altimur is starting a long journey that, depending on the equipment, could end up in any number of places. But for now, every load is a small victory, because as it rolls out the gates, the troops are one step closer to leaving Afghanistan. “Guys seem to be motivated to close this place down,” Feeney says, “because they know the faster they shut down Altimur, the faster they can go home.”